Generally, acrylonitrile-butadiene rubber-styrene (ABS) resin has excellent impact strength and processability as well as good mechanical strength, thermal deformation temperature, and gloss. Thus ABS resins are widely used in electrical and electronic components, office equipment and the like.
However, ABS resin used in the housings of the high-end home appliances such as LCDs, PDPs, TVs, and audio components can be easily scratched. Also it can be difficult to obtain a desired color and/or texture, which can reduce the product value.
To resolve these problems, the surfaces of ABS injection molding products can be coated with urethane paint, UV coating, or acrylic resin coating having high scratch resistance. However, these coatings are associated with additional complicated processing steps, which can increase defects, and which ultimately can reduce productivity due to the addition of the post processing steps. In addition, environmental pollution problems caused by the coatings cannot be completely avoided.
Therefore, there is a demand for a non-coated resin that can be prepared without a post processing step and can have good transparency and coloring properties to realize a high gloss color feeling.
Methyl methacrylate-acrylonitrile-butadiene-styrene (MABS)/polymethylmethacrylate (PMMA) materials can be used to produce luxury designs in housings of home appliances, such as TVs and monitors. Recently, the use of semi-transparent materials has expanded according to market trends. Further, with increasing design intricacies, the demand for high impact and high fluidity is also increasing.
In MABS/PMMA compositions, silicone-type impact reinforcing materials can be used to increase impact strength. In the case of semi-transparent materials, coloring agents can be added in minute quantities, which can lower the hiding power of color. Consequently, problems can occur due to whitening of the product surface when an injection molding product is left at a temperature of less than −30° C.
A g-MABS impact reinforcing material can be added to the composition in excess, instead of silicone-type impact reinforcing materials. However, this method can impair the impact reinforcing effect. Moreover, if an impact reinforcing material with a particle size more than 3000 Å is used, low temperature whitening can occur.
In addition, this method not only can cause low temperature whitening but can reduce the fluidity of the resin, which can reduce formability, and can also increase gas generation.